256 KSSAY XXIV. 



the volatile alkali ; and since as much of the earth must 

 be disengaged as the acid attracts of the alkali. If some 

 Glauber's ammoniac be first added to the solution of 

 magnesia, no precipitate will be occasioned by the caustic 

 alkali. 



P. 135. In my experiments, iron has never been pre- 

 cipitated, in its metallic form, from its solution in muriatic 

 acid by zinc. 



P. 149. The calx precipitated from the butter of 

 antimony by oyster shells is not a pure precipitate ; but, 

 according to my experiments, still contains some muriatic 

 acid. I could not accomplish the dulcification of muriatic 

 acid in the way mentioned by the author. 



P. 155. If much nitrous acid be taken for the solution 

 of quicksilver, and the whole be boiled together, the quick- 

 silver is completely calcined, and then it affords a white 

 precipitate, on addition of spirit of sal ammoniac. The 

 quicksilver in corrosive sublimate is in a calcined state ; 

 the black matter is nothing but exceedingly fine revivified 

 mercury. 



P. 177. It is said that platina is not precipitated by 

 mineral alkali ; but although many agree in this opinion 

 with the author, a precipitation does actually take place. 



P. 248. As the neutral salt consisting of lemon juice 

 and fixed alkali is capable of dissolving iron, it is no wonder 

 that alkali does not cause a precipitation. The same tiling 

 has been observed by the author (p. 303) concerning the 

 solution of iron in tartar, and the reason is the same. 



P. 273. The want of fixed air is said to be the cause 

 why acetated lead, prepared from minium, does not 

 crystallise ; but it is totally different. The author has 

 not mentioned that his solution, after he had introduced 

 fixed air to it by means of his apparatus, became white, 



